Scattered wave calculations

Copper porphyrin is one of the best-characterized of the metalloporphyrins, and its electron spin resonance (ESR) spectrum has been known for a quarter of a century.(17) More recently, electron nuclear double resonance (ENDOR) investigations have provided the complete hyperfine tensors for the metal, the nitrogens and the pyrrole protons.(18) We have used this detailed knowledge earlier(, ) to assess the quality of scattered-wave calculations. 

B. Self-consistent Field-A -Scattered-Wave Calculations. .. 5... 

A. F. Ramos, R. Arratia-Perez, and G. L. Malli, Phys. Rev. B, 35, 3790 (1987). Dirac Scattered-Wave Calculations on an Icosahedral Gold (Au13) Cluster. 

The cluster approach is, like the extended-surface approach, characterized by many different calculational schemes. A recent review stresses electronic aspects of bonding. In this review we have chosen to concentrate on geometric aspects. We shall discuss a number of major techniques in order of increasing computational complexity the extended H uckel theory, self-consistent Xa scattered wave calculations, and self-consistent ab initio Hartree-Fock and valence bond methods. In that order these techniques allow increasing accuracy. However, the cluster size must decrease simultaneously due to calculational complexity, ultimately reducing the degree of analogy with surfaces. 

Dietz, E. R. (1983). Scattered-wave calculations of the phosphorus L X-ray emission spectrum of ligand-substituted phosphorus oxyanions. J. Phys. B16, 4593-9. 

To apply these ideas, we have carried out scattered wave calculations... 

The electronic structure of tetrahedral oxyanions and their derivatives has been extensively studied by many authors during the past decades. The earlier attempts were summarized by Prins [1]. Since the work of Walsh [2] and that of Wolfsberg and Helmholz [3] several semi-empirical theoretical studies have been published [4-7]. Later ab initio [8-10] and scattered wave calculations [11] have been also reported. Among the experimental investigations, Prins mentioned the electron spin resonance measurements of radicals formed by ejection or addition of an electron from or to certain oxyanions, obtaining information on just those molecular orbitals which contained unpaired electrons. [12] X-ray absorption and emission studies provided usefial information on a limited number of molecular orbitals in the valence band [13-19]... 

A detailed analysis of the UV-VIS spectrum of (spinach) plasto-cyanin in the Cu(II) state has been reported (56). A Gaussian resolution of bands at 427, 468, 535, 599, 717, 781, and 926 nm is indicated in Fig. 7. Detailed assignments have been made from low-temperature optical absorption and magnetic circular dichroic (MCD) and CD spectra in conjunction with self-consistent field Xa-scattered wave calculations. The intense blue band at 600 nm is due to the S(Cys) pvr transition, which is intense because of the very good overlap between ground- and excited-state wave functions. Other transitions which are observed implicate, for example, the Met (427 nm) and His (468 nm) residues. These bonds are much less intense. The low energy of the d 2 orbital indicates a reasonable interaction between the Cu and S(Met), even at 2.9 A. It is concluded that the S(Cys)—Cu(II) bond makes a dominant contribution to the electronic structure of the active site, which is strongly influenced by the orientation of this residue by the... 

The theoretical treatments of other electrocatalytic reactions are very limited. Even semiquantitative treatments are important since they provide insight as to the role of adsorption sites and surface interactions involving reactants, intermediates, and/or products. Of special interest are theoretical treatments of the energetics of adsorption on various sites using molecular orbital and X- scattered wave calculations in combination with experimentally evaluated adsorption isotherms and in situ spectroscopic measurements on single-crystal electrode surfaces. 

The reactions of SFs at high temperatures and pressures with several carbon-sulphur and carbon-oxygen compounds have been reported. At temperatures above 485 °C and a pressure of 1360 atm, SF reacts with CS2 to yield (CF3)2S, (CF3)2S2, C, and S reaction at 500 °C and 270 atm with COS gives CF4, SOF2, and S. No reaction was observed with CO or CO2 below 500 C and 4000 atm. This lack of reaction was explained by the formation of SF4 via a co-ordinated intermediate (2), which decomposes to SF4. S.C,F.-X scattered-wave calculations... 

Self-consistent Dirac-Slater calculations of molecules and embedded clusters have been recently reviewed by Ellis and Goodman. Relativistic band structure calculations have also been carried out. Dirac scattered-wave calculations have been carried out on a number of inorganic complexes such as W(CO)fi and WjQg - The electronic structure and geometries of X2H2 (X = O,S, Sc and Te) have also been investigated recently. ... 

Yang, C.Y., 1983, Relativistic scattered-wave calculations for molecules and clusters in solids, in Relativistic Effects in Atoms, Molecules and Solids, NATO ASI Series, Series B Physics, Vol. 87, ed. G.L. Main (Plenum, New York) p. 335. 

Bis([8]annulene) complexes, lanthanide 84 Bis(cyclooctatetraene) complexes, cerium 84,88 Bis([8]annulene) complexes, cerium 84,88 Bis(cyclooctatetraene) cerate anion 85,88 Bis([8]annulene) cerate anion 85,88 Molecular orbital calculations 86 Xa Scattered-wave calculations 86 Quasi-relativistic Xa Scattered-wave calculations 86... 

High symmetry complexes, photoelectron spectroscopy [8]Annulene complexes, photoelectron spectroscopy Cyclooctatetraene complexes, photoelectron spectroscopy Xa scattered-wave calculations Cerocene... 

Uranium hexamethoxide, photoelectron spectroscopy Xa scattered-wave calculations, relativistic... 

Faucher, J.-R, Labarre, J.-F., and Shaw, R. A., Bonding in cyclophosphazenes. Quantum and experimental support for Dewar s island model, Z. Naturforsch., 31b, 677 (1976). Mitchell, K. A. R., Noodleman, L., and Paddock, N. L., Xa scattered wave calculations of the ionization energies of N3P3F6 and N4P4F8, Chem. Phys. Lett., 47, 265 (1977). Noodleman, L., Westwood, N. P. C., and Mitchell, K. A. R., Ionization energies and electronic structure of the cyclic phosphazene as determined by UV photoelectron spectroscopy and Xa scattered wave methods. Chem. Phys. Lett., 58, 252 (1978). 

Ab initio SCF-MO and SCF-X scattered wave calculations have been carried out on CpLi. A double pentahapto structure was predicted for dilithium pentalenide (14) u.v. irradiation of (14) provided the corresponding radical anion. The Li in solid [(n-CgH SiMeg)Li.TMED] is essentially trigonal bipyramidal, with... 

In the crystal structure of CpBeX (1, X=Cp) at 128 K, Be is disordered between two equivalent sites in each site Be is centrally bonded to one ring and peripherically bonded to the other, via a largely sp hybridised carbon. SCF-X scattered wave calculations on 1 (X=K or Cl) and i.r. spectra of 1 (X=C1, Br or Cp) were reported. The reaction of PhgAs CHg and MClg gave the chlorine bridged dimers, [PhgAsMClgMAsPhgJClg (M=Be or Mg). 

Quasi-relativistic Xa-scattered wave calculations on CpyAn-L compounds with L=H, CO, NO, OH, led to the conclusion that sigma bonding to the Ji-neutral, jr-acidic, and jt-basic ligands has essentially the same donation of electron density from the sigma orbital of the L ligand into a uranium orbital that is primarily 6dz2 in character. The 5f orbitals are responsible for back donation into the Ji orbitals of CO and NO. Acceptance of electron density from the n orbitals of OH involves the 6d orbitals (Bursten et al. 1989). 

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